169 replies to this topic

[oakmere]

With the alternators struggling with the higher revs being put through them might it be worth getting someone like TTV racing to produce an alternator under drive pulley? It could also be produced with 6 ribs for the SC boys. Dose anyone have a spare pulley not in use that could be sent off?

[leevx2.2]

Yes I have one in the garage as I changed to 6 rib do you fancy it

[oakmere]

Lee is this a pulley that fits onto the alternator?

[oakmere]

Sorry Lee got the wrong end of the stick. You have a spare std alternator pulley got it. I may be interested if others fancy a larger alternator pulley to reduce its rpm and reduce engine loads.

[leevx2.2]

Yes standered alternator pulley .

[JimmyJamJerusalem]

That sounds like a good idea! I'd be interested

[siztenboots]

an oversized alternator pulley would work

[oakmere]

Yes that is what I am talking about. By increasing the alternator pulley size you will reduce the number of RPMs which are much higher than engine rpm. This is a much safer way forward than messing with main engine damper pulley. A std pulley would need sending to TTV, not sure if they have a minimum order quantity. I will send them an e-mail and see what they say.

[CHILL Gone DUTCH]

Does anyone no what is a safe RPM for the alternator on standard pulley

[vocky]

atom X had one made from billet alloy, though I doubt he will reply to this thread

[oakmere]

Good news they already do some: Hi Martin thanks for your enquiry. We do have some larger vx220 alternator pulleys designed to slow down the alternator speed for competition use. 6 Groove belt type @ 54mm Diameter £45 + postage + vat 5 Groove at 70mm @70mm Diameter £50 + postage + vat I have these in stock

[Hark]

Does running a SC at stage 2 affect the life of the alternator due to increased stress on it?  

 

I had a new/re conditioned alternator about 18 months ago and I thing I can already hear it making an odd noise.  Can't have done more than 5000 miles.

[Exmantaa]

Good news they already do some: Hi Martin thanks for your enquiry. We do have some larger vx220 alternator pulleys designed to slow down the alternator speed for competition use. 6 Groove belt type @ 54mm Diameter £45 + postage + vat 5 Groove at 70mm @70mm Diameter £50 + postage + vat I have these in stock

 

You sure those are for the Z22SE engine?

Stock Z22SE alt pulley is around 57mm (sometimes less due to wear)

@7K rpm that spins the Alt to around 20K. And that's a lot for an alternator...

I don't have the exact numbers here, but for a ~7.3Krpm engine a diameter of 61-62mm is good without loosing much capacity at idle. A 65mm pulley will be good for a sub 8K engine.

 

So that 6-rib is too small and their 5 rib too big...

What material are they?

[Bargi]

Does running a SC at stage 2 affect the life of the alternator due to increased stress on it?     I had a new/re conditioned alternator about 18 months ago and I thing I can already hear it making an odd noise.  Can't have done more than 5000 miles.

No its the RPM thats being done, if your getting funny noises and its newish I'd say its prob the tensioner

[oakmere]

I have forwarded the questions. Is the turbo alternator the same as the N/A?

[Hark]

Belt tensioner? Already chanted that as the bearing was shot.. Different noise though.

[oakmere]

The material is 6082 Aluminium. The 70mm is used in the US for circuit racing so probably too large for the road. Would a 63mm be the best compromise? Should I get a quote for 5 and 6 peak? Could a 6 peak be used for both? Just trying to simplify things.

[CHILL Gone DUTCH]

The charger pulley is 6 so should be ok on alternator To if they line up ok

[Exmantaa]

The material is 6082 Aluminium. The 70mm is used in the US for circuit racing so probably too large for the road. Would a 63mm be the best compromise? Should I get a quote for 5 and 6 peak? Could a 6 peak be used for both? Just trying to simplify things.

 

A 63 to 65mm would be good. And only a 6 rib version should be enough, as you can simply use the inner 5 ribs like the SC pulley. (so add 1 rib to outside of the OEM pulley)

I like my aluminium pulleys hard anodized to minimize wear, but maybe as option?

Edited by Exmantaa, 02 September 2013 - 09:33 PM.

[oakmere]

Just a quick calculation shows that a 65mm pulley would reduce the rpm by 12%. Dose that sound correct? This dose not sound like very much, dropping std idle rpm from 2285 to 2011 rpm. The 70mm would drop idle speed to 1870 is this too slow?